package com.bjpowernode;

import com.sun.org.apache.bcel.internal.generic.PUTFIELD;
import org.springframework.boot.autoconfigure.SpringBootApplication;

import java.util.Collection;
import java.util.Comparator;
import java.util.Hashtable;
import java.util.TreeMap;
import java.util.concurrent.ConcurrentHashMap;


public interface aaa  {

    public static void main(String[] args) {

        ConcurrentHashMap a =new ConcurrentHashMap();

    }
}
